Fabrication of Micro -Tool Using Electrochemical Micro-Machining and Study of Process Parameters

Recent changes in societies demand have forced us to introduce more and more micro-parts into various types of industrial products for example, the fuel injection nozzle for automobiles, miniaturized medical tools, microprobe used to measure electricity or surface properties of a test piece, integrated micro channels used as medicine delivering systems and various aeronautical requirements. In the present work, an experimental set up has been designed and developed to fabricate micro electrodes and to machine micro holes and slots using the ECMM process and to study the effect of various process parameters on it. The machining of micro holes and slots is done on copper work pieces of 60 μm and 500 μm thickness using ECMM and copper wire of dia. 200 μm as tool. The effect of process parameters such as voltage, electrolyte concentration, pulse duty ratio and feed rate on machined hole diameter have been studied. The hole dia. increases exponentially with voltage and concentration and decreases exponentially with feed rate. The fabrication of straight micro tools is done on the same set up using dipped ECM with copper wire of dia. 1.3 mm and copper sheets of 3 mm thickness and holes of various diameters as cathodes. Same method is used to fabricate step micro tools with copper wire of dia. 2 mm. The effect of process parameters namely voltage, IEG, time, pulse duty ratio and electrolyte concentration on the diameter of the micro tool is studied. The change in diameter of the tool increases linearly with voltage and time while it increases quadratically with pulse duty ratio and electrolyte concentration. The photographs of all the micro tools are taken and measured using USB microscope at 50x and 200x zoom